Alcoa (AA -3%) kicks off earnings season after the close, and its results “will show the limits...

Alcoa (AA-3%) kicks off earnings season after the close, and its results “will show the limits of even the most ruthlessly efficient organization in the face of a challenging economy.” Analysts will want to hear more about Alcoa’s biggest problem: China. Increased output has created an aluminum glut that’s been squeezing smelting margins.